1. Field of the Invention
The present invention relates to a side mold working mechanism, and more particularly to a side mold working mechanism capable of locating a slide thereof for preventing undue return of the slide.
2. The Related Art
Generally speaking, a plastic product is shaped in a main mold through a method of injection molding. But if the plastic product needs to define a hole or a cavity thereon, a side mold is provided to mate with the main mold to shape the hole or the cavity on the plastic product.
The side mold includes a slide, a pair of guide blocks and an angular pin. The slide disposes a shaping member at the front thereof to be inserted in the main mold for shaping the hole or the cavity on the plastic product when the plastic product is formed in the main mold. As the plastic product becomes more and more compact, the slide correspondingly becomes smaller according with the compact plastic product. The slide is driven moving along leading tracks defined on the guide blocks by the angular pin fixed on a top clamping plate and a spring. When the angular pin is drawn out from the slide completely, the slide moves backward continually because of the elastic force of the spring and so the slide is prone to returning unduly, which brings a bad influence on the following shaping processes of the plastic product. Conventionally, in order to solve the problem, locating screws are disposed in the rear of the slide or locating bearings are disposed on the top of a cavity insert to engage with the slide for limiting the return travel of the slide. However, because the slide is quite small, the slide has no space to mount the locating screws or to couple with the locating bearings. If the locating screws are disposed in the slide constrainedly, the intensity of the slide becomes weak, which influences the quality of the plastic product and the using lift of the slide.